python - pytest 是否限制自定义命令行参数中的所有小写选项？

Question

我正在尝试从 argparse.ArgumentParser 移植一些命令行参数实例到等效的 pytest conftest.py文件使用 pytest 的 pytest_addoption
查看 pytest 帮助功能，我发现 12 个使用过的单字符短选项，即 k, m, x, c, s, v, q, r, l, h, p, o

MacBook-Pro:~ user$ pytest --help | grep " -[a-z]"
  -k EXPRESSION         only run tests which match the given substring
                        -k 'test_method or test_other' matches all test
                        'test_method' or 'test_other', while -k 'not
  -m MARKEXPR           only run tests matching given mark expression.
                        example: -m 'mark1 and not mark2'.
  -x, --exitfirst       exit instantly on first error or failed test.
  -c file               load configuration from `file` instead of trying to
  -s                    shortcut for --capture=no.
  -v, --verbose         increase verbosity.
  -q, --quiet           decrease verbosity.
  -r chars              show extra test summary info as specified by chars
  -l, --showlocals      show locals in tracebacks (disabled by default).
  -h, --help            show help message and configuration info
  -p name               early-load given plugin (multi-allowed). To avoid
  -o [OVERRIDE_INI [OVERRIDE_INI ...]], --override-ini=[OVERRIDE_INI [OVERRIDE_INI ...]]

然而，如果我尝试在该集合之外定义一个选项，我会收到以下异常

def pytest_addoption(parser):
    parser.addoption('-b', '--build_special' )


  File "/Library/Python/2.7/site-packages/_pytest/config/argparsing.py", line 72, in addoption
    self._anonymous.addoption(*opts, **attrs)
  File "/Library/Python/2.7/site-packages/_pytest/config/argparsing.py", line 305, in addoption
    self._addoption_instance(option, shortupper=False)
  File "/Library/Python/2.7/site-packages/_pytest/config/argparsing.py", line 315, in _addoption_instance
    raise ValueError("lowercase shortoptions reserved")
ValueError: lowercase shortoptions reserved

无论我选择哪个角色，这似乎都是这种情况，这让我认为这只是行为受限的时期。

问题:pytest 是否限制短选项的任何和所有使用？

我有点困惑，因为当你查看相关的 pytest source

def addoption(self, *opts, **attrs):
    """ register a command line option.
    :opts: option names, can be short or long options.
    :attrs: same attributes which the ``add_option()`` function of the
       `argparse library
       <http://docs.python.org/2/library/argparse.html>`_
       accepts.
    After command line parsing options are available on the pytest config
    object via ``config.option.NAME`` where ``NAME`` is usually set
    by passing a ``dest`` attribute, for example
    ``addoption("--long", dest="NAME", ...)``.
    """
    self._anonymous.addoption(*opts, **attrs)

似乎暗示我可以使用与 argparse 的 add_option 完全相同的语法，这在 argparse documentation 中足够有趣。提到

Replace all optparse.OptionParser.add_option() calls with ArgumentParser.add_argument() calls.

和 add_argument documentation明确列出允许的单个标志选项:

The add_argument() method must know whether an optional argument, like -f or --foo, or a positional argument, like a list of filenames, is expected. The first arguments passed to add_argument() must therefore be either a series of flags, or a simple argument name. For example, an optional argument could be created like:

>>> parser.add_argument('-f', '--foo')

Answer 1

从pytest源代码...

/src/_pytest/config/argparsing.py

def _addoption_instance(self, option: "Argument", shortupper: bool = False) -> None:
    if not shortupper:
        for opt in option._short_opts:
            if opt[0] == "-" and opt[1].islower():
                raise ValueError("lowercase shortoptions reserved")
    if self.parser:
        self.parser.processoption(option)
    self.options.append(option)

是的，他们限制所有小写的短选项